Subj : Re: first filter change To : All From : Ron Hansen Date : Wed Jul 09 2003 08:35 am I was unable to find a picture of your filter on the web so I'll make some assumptions. Does your media consist of a sponge or pad with a separate package of carbon (or no carbon)? If so, take a bowl of water out of the tank and scrub off the pad/sponge in that water and then put it back into the filter (and throw out the water). This kind of media doesn't really ever need to be changed. By doing this, you keep a substantial amount of the nitrifying bacteria that currently reside in the pad. Note: DO NOT rinse it in tapwater. Tapwater contains chlorine and/or chloramine and that will kill the bacteria. If your media contains carbon as well, then you'll have to replace it (if you want to use carbon). Nitrifying bacteria grows on all surfaces in the tank, not just in the filter. There is a high concentration in the filter because it is designed to have a large surface area, and it has a constant flow of water with dissolved oxygen for the bacteria to eat. Pulling out the media won't eliminate all the bacteria, but it will take out a sizeable percentage and it takes time for the new filter to become established. In large systems with many fish and a large bioload, many aquarists get around this problem by using multi-part filters. One filter gives mechanical filtration and another gives biological filtration. The mechanical filter media is changed whenever dirty, but the biological filter is never disturbed. Examples of biological-only filters are wet/dry filters and fluidized bed filters (sand filters). These are generally considered for "advanced" aquarists not because they are difficult to setup or maintain, but because they are expensive. One relatively inexpensive alternative is a filter equipped with a biowheel. This biowheel performs the biological filtration while a separate pad performs mechanical filtration. Another alternative is the AquaClear line of filters. They contain a sponge that you can rinse out, and a separate carbon pack. They work well and many swear by them. Now, on to maintenance. A proper schedule for you is to clean or replace your mechanical filter media whenever it is clogged and the water is bypassing it. For most people, this is every 2-4 weeks. Your carbon pack is only good for about 2 weeks before it stops absorbing chemicals. You should be changing 10% (3 gallons) of water every week. Nitrates are the end product of the Nitrification cycle that is possible in most aquariums. Food rots and fish poop and pee and this produces ammonia (toxic to the fish). Bacteria break down the ammonia, but give off Nitrite (more toxic to the fish). Other bacteria break down the Nitrite and give off Nitrate (much less toxic to the fish). No process in a typical tank will consume the Nitrate. Therefore, you need to get rid of it. By changing 10% of the water each week, you will dilute the Nitrate and reduce the levels. If you don't, your fish will eventually die. Important: you should use a water conditioner such as Aquasafe to eliminate the chlorine and chloramines, or you will clobber your biofilter. It's usually better to add the conditioner to the water before adding the water to the tank (ie in a bucket). I hope this helps. "ruprecte" wrote: >Hey all, its been six weeks and I think its time that I change out my media. >My question is this: should I rub off some of the bacteria from the old >media onto the new one before replacing, or should there be enough >beneficial bacteria already existing within the tank that will collonize on >the new media. Im using a aqua tech 10-20 power filter in a 29g tank. The >tank has been up and running for six weeks now and somehow is still reading >nitrate levels at being 20-30. Im assuming that this is due to the extended >time that Ive let the original media stay in there, to me this seems to be >the only possible reason that the levels are so high, ammonia is low-close >to non-existant and there are five large plants+12 fish that have all been >in there for the last six weeks..no new additions and no losses.Thanks for >any imput.-Brian > > > > >-----= Posted via Newsfeeds.Com, Uncensored Usenet News =----- >http://www.newsfeeds.com - The #1 Newsgroup Service in the World! >-----== Over 80,000 Newsgroups - 16 Different Servers! =----- --- þ RIMEGate(tm)/RGXPost V1.14 at BBSWORLD * Info@bbsworld.com --- * RIMEGate(tm)V10.2áÿ* RelayNet(tm) NNTP Gateway * MoonDog BBS * RgateImp.MoonDog.BBS at 7/9/03 7:35:03 AM --- PCBoard (R) v15.3/M 100 * Origin: MoonDog BBS, Brooklyn,NY, 718 692-2498, 1:278/230 (1:278/230) .